Means and method for making carbide tipped saws



C. E. DRAKE March 23, 1954 5 Sheets-Sheet l Filed May 18, 195C lill!filloll ti w l m m Ow O IIIL I IP l I l. afm, I I- I I NQ @N wm .A

INVEN'I'OR .CLAUD E. DRAKE ATTORNEY C. E. DRAKE March 23, 1954 MEANS ANDMETHOD FOR MAKING CARBIDE TIPPED SAWS Filed May 18, 1950 5 Sheets-Sheet2 NSW HM -A Nml mw. l S

.N .0E E

INVENTOR CLAUD E. DRAKE ATTORNEY March 23, 195,4

C. E. DRAKE MEANS AND METHOD FOR MAKING CARBIDE TIPPED SAWS Filed May18, 195C 5 Sheets-Sheet 3 FIG. 6. l f// 7a /23 f# I 7 w a T l Il @YT ,Wff/5 1/ 7 w ff; l/af 7 6 l l I l l la I FIG. 9.

FIG. I2

INVENTOR CLAUD E. DRAKE E* www ATTORNEY March 23, 1954 c. E. DRAKE2,673,279

MEANS AND METHOD FOR MAKING CARBIDE TIPPED sAws INVENTOR CLAUD E. DRAKEATTORNEY March 23, 1954 Q E DRAKE 2,673,279

MEANS AND METHOD FOR MAKING CARBIDE TIPPED SAWS Filed May 18, 1950 5Sheets-Sheet 5 JNVENToR.

E DRAKE ATTORNEY Patented Mar. 23, 1954 UNITED STATES PATENT OFFICEMEANS AND METHOD FOR MAKING CARBIDE TIPPED SAWS 7 Claims.

This invention relates in general to certain new and useful improvementsin means and methods for making carbide tipped saws and the like.

Heretofore, carbide tipped cutting tools, such as circular saws, millingcutters, and the like, have been manufactured by blanking out orotherwise forming the steel plate or disc comprising the body of thecutter. The teeth are suitably recessed, either in the original blankingoperation or by subsequent grinding, and slugs of sintered carbide orother heavy dense alloy tipping material are then manually set intoplace and clamped or otherwise held in such position while being brazedwith an oxyacetylene torch or similar device. The brazing is usuallydone with either silver solder, tobin bronze, copper sandwich alloy, andconventional iiuxing agents. Thereafter, the carbide tips are eachsuccessively ground to conform to the desired tooth pattern.

This method has proved extremely costly, both in l terms of material andlabor, since the slug of tipping material is usually substantiallylarger than necessary and, therefore, a good portion of it is wastedduring the grinding operation; and because it is necessary to grind agood deal of the slug of tipping material away at relatively slowspeeds, because of its hardness and other physical characteristics, agreat deal o time and labor is unnecessarily expended. As has been morefully described in my copending applications appreciable economy andmuch improved efciency in the cutting operations of the cutter itselfcan be achieved by employing pre-formed tips of precisely engineeredshape and design. This procedure, however, requires a degree of accuracyin tip placement and retention during the brazing operation which hasbeen thought impossible of attainment by existing methods.

Another and quite different problem encountered in the above-describedmanual method of carbide tipping is also due to inherent difficulties inall manual methods; that is to say lack of uniformity in execution ofthe procedure involved. For example, the workmen in setting the tippingslug in place will ordinarily apply more or less pressure to theclamping devices which hold the tooth in place, so that at the instantduring which the brazing material begins to flow and the brazing jointis being formed a greater or lesser degree of the molten metal will besqueezed out of the joint. This lack oi uniformity leads to a ratherhigh incidence of tip loss when the cutter is actually subjected to theworking conditions under which it must operate.

Finally, the use of heat generating means, such 2 as oxyacetylene andoxyhydrogen torches, introduce further problems which are inherent inany operation employing such heating means. The heat cannot be appliedwith precise uniformity to each successive tooth, nor can it besuiciently localized to prevent extensive thermal changes from takingplace around the rim of the saw. Because all circular saw plates andsimilal1 types of cutters must undergo an extensive and painstakingtensioning operation so that they will run true at high speeds, thepenetration of heat inwardly from the region of the tip into the body ofthe saw plate creates new and different stresses than those present inthe saw immediately after it has been tensioned. Therefore, carbide tipsaws and cutters, which have been tensioned by conventional manualmethods, frequently do not run true and often tend to develop rim cracksand other defects which seriously impair the life and efficiency of thesaw or cutter.

It is, therefore, the primary object of the present invention to providemethods and means for brazing tips into circular saws and similar typesof cutters, whereby the tips may be accurately set i. in place with ahigh degree of uniformity as to position, size, degree of thickness ofsolder-film and with an exceedingly rapid and precisely localizedapplication of brazing heat. It is a further object of the presentinvention to provide means for brazing carbide and other dense alloytips into circular saws and similar types of cutters by the use ofelectronically applied heat energy.

It is a further object of the present invention to provide means formechanically setting and holding tips in place during brazing to producea tipped saw or cutter having tooth-tips which are uniformly andaccurately brazed into position.

It is also an object of the present invention to provide an electronicsaw tip brazing machine which is simple and economical in construction,use and maintenance, and very materially reduces the labor cost inmanufacturing such saws and cutters.

With the above and other objects in View, my invention resides in thenovel features of form, construction, arrangement, and combination ofparts presently described and pointed out in the`r Figure 3 is afragmentary sectional view taken along line 3--3 of Figure 1;

Figures 4 and i5 are fragmentary sectional views taken along line 4--4and 5-5, respectively, of Figure 2;

Figure 6 is a fragmentary sectional view taken along line 6 6 of Figure5;

Figure 7 is a fragmentary sectional view taken along line 'I-l o'fFigure 6;

Figure "8 is a fragmentary sectional view taken along line 8-8 of Figure7;

Figure 9 is a fragmentary sectional view taken along line 9-9 of Figure1;

Figure 10 is a fragmentary sectional view taken along line IU-IIl ofFigure 9;

Figure 11 is a fragmentary sectional view taken along line II-II ofFigure 10; n l p Figure 12 is an enlarged top plan view of thetransverse-position indicating scale forming a part of the presentinvention;

Figure 13 is a fragmentary sectional view taken along line ISL-I3 ofFigure `1;

Figure 14 is a fragmentary sectional View taken along line I4-I4 ofFigure `2;

Figures 15, 16 and 17 are fragmentary sectional views taken,respectively, along lines I|5,

I6'-`-I6, and `II-I oi Figure 14;

Figures 18 and `19 are fragmentary sectional viewsvtaken, respectively.along lines I8-I8 and I'S-IB of Figure 17;

Figure 20 is a 'fragmentary sectional view taken along line 20e-23 ofFigure 1;

Figure 21 is an exploded View of the tip holder forming a part of thepresent invention;

Figure 22 isa top plan View of the tip holding assembly;

Figure 23 is a bottom plan view of the tip holding assembly;

-Fig'ure 24 is a fragmentary perspective view of the lower end of thetip holding magazine forming -a part of the present invention;

Fig-ure 25 is a perspecitve view of the retention spring employed in thetip holding magazine;

Figure `26 is a fragmentary sectional view taken along line 2B-2B ofFigure 5;

Figure 27 is a fragmentary sectional view taken along `line 21--2-7 ofFigure 26; and

`Figure 2'8 is ya fragmentary sectional view taken along line 28-28 ofFigure 1.

Referring now in more detail and by reference characters to thedrawings, Ardesignates an electronicbrazing machine comprising aconventional base frame I, which may be supported from the floor, wallorVany other suitable structure as may be desired. Bolted to the baseframe I and extending vertically upward therefrom is la face plate 2,provided upon its forwardly presented face with a horizontally extendingdovetail way 3 jfor supporting a horizontally shiftable dovetail slide4. Threadedly mounted in and extending through the inwardly projectingintegral lug 5, formed on the inside face of the slide 4, is ahorizontal adjustment screw 6, suitably lbearing at its one end in acollar 'i formed integrally withthe way 3. The screw E projects throughand outwardly of the collar 1 and is provided at its end with adiametrally projecting pin 8 for `reciving a handle or crank 9.

The slide 4 is provided upon its outwardly presented face with avertical -dovetail way IU for lreceiving a vertically shiftable dovetailslide H. `Journaled in and extending through an integ'ral Aboss I2,`formed on the `rear face of the slide "If'I Vandheldagainst verticalmovement with respect thereto by set collars I3, 14, 4is a vertical'adjustment screw I5 threadedly extending through an internally threadedboss Il, formed integrally on the slide 4. At its upper end the screw I5projects above the slide II and is provided, on such projecting end,with a diametral pin I8 for engagement with the handle 9. It may benoted in this connection that the projecting ends of the screws 6, I5and their respective pins 8, I8 are of the same size -so that the handle9 may be interchangeably used with either V'of them.

Formed integrally with and projecting laterally from one side face ofthe slide II is a spindle supporting arm I9, having a forwardlyprojecting cylindrical boss 20, and the latter being in turn providedwith a concentrically bored circular recess 2I. Rotatably mounted in andextending axiallyI forwardly from the recess 2| is a worksupportingspindle 22 supported and held in place by ball bearings 23, operativelymounted between a rotating ball-race 24 and a stationary ball-race 25,the latter 'being held in place -by an annular retainer ring -26vmounted upon the outer face of the boss 20 Vby means of counter-sunkscrews 21. Formed integrally with the work-supporting spindle 22 is adiametrally enlarged collar 23 disposed abuttingly -against the end faceof the rotating ball-race 24. On its Voutwardly presented face thecollar 2B abuts against a cylindrical cap plate 29 having a rearwardlyextending skirt 3|) snugly overlying the outer cylindrical surface ofthe boss 20 and being provided with an oil soaked felt sealing ring 3lfor protectingly enclosing the ball bearings 23. The cap plate y29 isconcentrically bored, as at 32, for snug-fitting engagement with adiametrally reduced secondary collar 33 integrally 'formed as a part 'ofthe work-supporting spindle 22 iniorwardly spaced relation to the collar28. On its outer end, the work-supporting spindle 2'2 is threaded forreceivin'g a retainer nut 34, which bears against a work-clamping cap 35having an annular skirt 36 adapted to bear against the outer face of thesaw plate Si, which is thus clamped tightly against the face of the capplate 29. As will be noted by reference to Figure 4, the projecting endof the Work-supporting spindle 22 is substantially smaller in diametralsize than the saw hole h and is, therefore, provided with 'a tubularbushing 31 which is of sufficient axial length to fit neatly, but nottightly, between the collar 23 and the inner face of the work-clampingface 25. The bushing 37 is further provided with an annular v'flange V38sized to fit precisely within the saw hole h and support the saw plate Sin concentric position upon the spindle 22. Threadedly mounted in and`extending horizontally forwardly from the front or vertical face of thearm I9 is a guide pin 22 disposed inoutwardly spaced parallel relationto the worksupporting spindle`22 and provided at its outer end with aguide-head g'and a lock washer 23. The lock washer 23' can be loosenedand the guide pin '22 threaded in or out, so `that 'the guide-head gwill contact the rear face of the saw `plate at some selected position'of valignment. Thereupon, the lock nut 23' can `be threaded downtightly against 'the outer face of the arm I9 to `hold the guide vpin 22in such adjusted position. Also threadedly mounted in and extendinghorizontally forwardly `from 'the slide II in upwardly spaced parallelrelation to both the guide .pin 22 and the work-supporting spindle 22 isa second guide pin 22" provided with a lock washer23" and arm24.Suitablysecured upon the lower end of the arm 24 and :projectinginwardly therefrom is a guide-head g' adapted to be swung down intoaxial alignment with the guide-head g. The second guide pin 22" can beadjusted in or out, as the case may be, dependent upon the thickness ofthe saw plate S, so as to lightly contact the outer face thereof. Whenthe guide pins 22', 22, are properly adjusted, the periphery of the sawplate S which is being tipped will always be held in a selected positionin reference to its distance outwardly from the outer vertical face ofthe armr I9. It, of course, will be obvious that the adjustment of thetwo guide-heads y, g', will be such that the saw plate S will not betightly gripped or bound thereby and can slide freely therebetween as itis rotated. However, since the spindle '22 floats parallel to its axis,this spindle 22 will move inwardly or outwardly slightly in an axialdirection, if necessary, to compensate for any warpage or wabble whichmay exist in the saw plate S.

Also bolted to the base frame i and extending vertically upwardlytherefrom in laterally spaced relation to the plate 2 is a secondaryface plate 39 provided upon its forward face with a heavy, rigid bracketmember 40 integrally including a horizontal base plate 4l supported bytriangular webs 42. Formed in the upper horizontal face of the baseplate 4l is a dove-tail way f1.3 extending outwardly at 90 to the planeof the face plate 39 for shiftably supporting a dovetail slide 44.Formed integrally on the outer lateral margin of the slide 44 is anangularly upstanding arm 45 integrally supported by triangular gussets43. It will be noted by reference to Figures l and 14 that the outerface 4l of the arm 45 is machined oif to an angle of approximately 30 tothe vertical and that the subjacent portion of the bracket web 42 issimilarly machined off to provide an undercut clearance space. It, ofcourse, should be noted in this connection that there is nothingcritical about the angle of 30, as will be presently more fullydiscussed.

Mounted in and extending through the arm 45 is the diametrally reducedthreaded end 48 of a spindle post 49 held in place by a lock nut 50.Mounted upon the spindle post 49 between endspacing washers 5|, 52, andheld in spaced relation by a bushing 53 are stationary ball-races 54,55, for operatively supporting ball-bearings 55 which carry rotatingraces 51, 58, the latter being, in turn, press-fitted intoconcentrically counterbored recesses 59, 50, against an internal spacingshoulder 3| of a rotating head 52. The head 62 is of frusto-conicalshape having an annular outer face t3 which is preferably at acomplementary angle of 60 to the arm face ill, so that the uppermostportion of the face 63 will be tangent to a horizontal plane. Atsuitably spaced, preferably uniform, intervals around the face 63 of thehead 62 are axial slots 04 each provided With a locking wedge 65 held inplace by machine-screws E6 for retentively gripping tipholding fingersG1.

Each tip-holding nger 61, as shown in Figures 21, 22, and 23, is formedpreferably, though not necessarily, of aluminum, bronze, or some othersuitable material which does not readily bond to the tip material whenthe braze is being made, and comprises a body element 03 integrallyincluding a shank 39, an upstanding heel-block 10, and a forwardlyextending side plate 'H previded along its upper inner margin with anangle-shaped groove 12 and being tapered at its outer end, as at 13. Onits inner face 14, below 6 the groove 12, the side plate 1| is providedwith a pair of longitudinally spaced pins 15. kThe shank 69 of the bodyelement 6B is of suiiicient length to nt within and project at one endbeyond the slot 54 and at such projecting end is provided with aninclined end-face l5, which is, in turn, provided with an indexinggroove Tl. Provided for co-operation with the body element 68 is aoating side plate 18 having an integral flangelike rib 'le which fitsslidably into the groove 12 and is cut away at its forward end, as at80. At its forward end, the side plate 18 is also tapered, as at 8i, tomatch the tapered portion 1.3 of the side plate 'il and intermediate itsends is provided with a pair of axially aligned elongated slots a2adapted for snug-ntting longitudinally shiftable engagement upon thepins l5. The side plate 'f8 is finally provided in its outer face with atransversely extending slot 83 for receiving the free end 3@ of awish-bone spring 85, which is, v

in turn, provided at its other end with a flat ilange 85 apertured, asat 3l, for securement upon the heel-block l0 by means of a machine screw88, which is threaded into a tapped hole 89.

When the tip-holding nger Sil is assembled, 'asv upwardly and outwardlyopening rectangularre-` cess sized for receiving the prism-shapedcarbide or dense alloy saw tip which is molded to rather precisetolerance in a predetermined shape to fit correspondingly shapedrecesses r formed in the teeth of the saw plate S. `Since the saw tipsa: are molded and sintered, it is impossible, even by the most rigidprecautions, to achieve a closer tolerance than 1.001. The floating sideplate l', however, is cap-able of shifting rearwardly or outwardlyseveral thousandths of an inch to accommodate for these variations andthe outer edges of the recesses 90 are chamfered orf slightly tofacilitate the entrance into the recess 90 of tips x, which are slightlywider than normal. Actually, the tip-holding recess 90 is deliberatelymachined to a slightly undersized dimension with reference to thedesigned width of the tips so that every tip a: will push the floatingside plate 18 outwardly a slight distance against the tension of thewish-bone spring 85, thereby insuring that each tip x is gripped snuglywithin the recess S0.

Preferably, though not necessarily, the side plate -H is provided with avertical aperture 9| extending therethrough from top to bottom andopening upon the under face of the groove 'l2 merely for Ventilating andheat dissipating purposes. This venting aperture 9| is desirable sincethe projecting end of the tip-holding nger 6l is in the heated zonewhile the braze is being made, as will be presently more fullydiscussed. It should be noted in 'this connection that the tip holdingfingers 31 project outwardly from the slots '54 s0 that the tipretaining recess 533 is completely in the clear. Because of the angularrelationship between the frusto-conical side face 53 of the rotatinghead 62 and the axis of the spindle post 49, each tip holding linger @lwill be substantiallyl horizontal when the head 62 is rotated to bringit up on top and when the head l52 is rotated kto bring it down to thebottom it will be almost vertical and will be carried into an opentopped rectangular pan 92 supplied with water from supply lines 93 tomaintain a Water-level such that the andere 7. tip-holding fingers 61'when disposed downwardly will dip down thereinto. .immersed in the wateris a conventional electric heater 94 whichisthermostatically controlledto keep the water warm, alli for the purposesA presently more fullyappeering.

Thetip holding fingers 61 do not extend all the way into the slots 64hence the rearward ends thereof are open for detent-forming engagementwith a relatively large ball 95 retentively held in the peened-down,open end of a tubular socketi rshell 95 which is externally threaded andthus mountedin an angularly bent flange lportion 91 of a supportingbracket 98 which is in turn bolted upon an adjacent side face of the arm45. The socket-shell 96 is integrally provided with an end wall` 99 andthreaded therethrough is an adjustment screw seated at its inner end inone end of a compression spring |0| which is, in turn, at its other end,seated against the ball 95 which thereby functions as a resilientindexer in cooperation with the several slots 64, as will present- -lybemore fully described.

Held securely upon the outwardly projecting end of the spindle post 49by means of a nut |02 is` a radially upwardly projecting bracket|.032having an angular flange |04 to which is bolted a block |05 havinga slot |05 extending therethrough. Bolted or otherwise suitably securedupon the outer end. face |01 of the block |05 in alignment with the slot|06 isa tubular plunger shell |08 for operatively receiving a springpressed plunger |09 which projects at one end outwardly therefrom and isprovided on such projecting end.

with a finger knob |"I0 and at its other end the plunger |09 enters andsnugly but slidably fits the slot |00. Formed in the block |05 adjacentthe face I I thereof is a vertically extending chamber II'2I ofrectangular cross sectional shape for receiving the lower end of a tipmagazine I3 comprising a long metal bar ||4 transversely milled off'along' one of its flat faces adjacent its ends to provide clipretention faces ||5. Upon its oppositefiat face the bar |4islongitudinally milled outA to provide an open ended groove or slot IIEsized for loosely accommodating a substantial supply of stacked tips x.The lower end of the groovey Ilopens into a` transverse discharge slotI'I1 and theside face of the bar |I4 is kerfed to provide a short slot|||l` opening into the discharge slot ||1 for receiving the U-shaped endportion |.I9 of a drag 4spring |20r which is bent over atlthe remote endof its shank in the provision of a tail piece |2| for insertion into alretention recess |22 formed in the bar II4. Removably disposed over theretention faces 5 and extendingaround the ends and across the groovedface-of the bar II4, is a spring bronze clip |23 which serves as aclosure for the groove I IB; The magazine may be loaded by removal ofthe clip |23 and when. loaded, the latter may be replaced toretain thetips a: in place. The magazine may then be slipped snugly into placewithin the chamber II2. It willv be noted by reference to Figure '7 thatthe floor of the chamber I`|2fis cut down slightly below the lowersurface of the plunger |09 to allow for. the thickness of the bottomflange of the clip |23. Thus,.the lowermost saw tip :c within themagazine I3 is located directly in front of the plunger |09 and.further'- more, is retained within the magazine I3 againstunauthorizedremoval by the end portion H9 of the spring |20.

I'hebracket |031`isvprovidedwith a threaded aperture |24-:l locatedbelow` theV fiance I 04' with l.

8'. its center on the radial line extending from the center of thespindle `post 49 and intersecting the center line of the magazine grooveI'I57. Threadedly mounted in an extending through the aperture |24 is arotary pintle I25integrally provided on its outer end with a rightangular handle I2 9` and locked in any selected position ofrotation by alock nut |21. Drilled eccentrically into the end face |28of the pintle|25 isa cylindrica1 bore |29, the axis of which is parallel tothe axisof the pintle |25 and the outeror end margins of which are peened overas at |30 to retain a large ball |3I resiliently urged outwardly by thecompression spring |132. The ball` I3I is adapted to ride partially intothe lower outwardly presented portion of each slot 64 as the head` 62 isrotated so that the tip holding finger` 61.*in1

such slot64 will 'be indexed accurately into alignment with thelongitudinal center line of thev tip n: which is in the magazine |I3ready to be` ejected therefrom upon manipulation of the plunger |09.

Since Various types of saw plates are of variousv thickness or gauge asit is called, it is necessary v to be able to handle tips x in any ofthe corresponding widths. are of standard outside dimensions so as tofit interchangeably into the chamber |I2 butv the grooves IIB are ofdifferent sizes. Thus, one magazine I3 with an appropriately dimensionedgroove H6 will accommodate tips for 14 gauge saws, another magazine I I3withan appropriately sized groove II6 will accommodate tips for l2 gaugesaws and so on. As has been stated, however, there is some appreciablevariationV irrsize within tips of any given gauge so the groove IIB* anddischarge slot |I1` must be slightly oversized.-

and these variations are rendered unimportant as each tip :cis ejectedresponsive to operation of the plunger |09 since the U-shaped end |I9 ofthe spring |29 forces each outwardly moving tip .r against the insideface ofthe clip |23 asia'w uniform and xed plane of reference'. Thismeans that the center line of the different-grooves |I'6 will not alwayscoincide precisely with the. center line of the tip holding fingers 61.This variation may be compensated by loosening the lock nut.

|21 and swinging the handle I2E`` to rotate. the pintlev |25 displacingthe ball |3| eccentrically to one side or the other of the` true centerline so that when the head is brought to rest with one of the tipholding fingers 61 in front of the magazine H3; the center line of suchtip holding finger 61 and the center line of the tip :c will besubstantially zo-incident. ment ismade for a particular magazineII3,.the lock nut |21 may be tightened: down and the proper alignmentwill remain fixed as long as tips are being dispensed from that magazine|I3 or any other magazine I I3 ofthe same gauge.

Mounted upon the top face of the arm 45 by means of bolts I33is asupport block |34 and a solderl feeding head |35 having an inclinednoseportion |36. Bolted upon the under'face of the solder feeding head |35is a fiat plate |31extend ing at its forward end |33 outwardly beyondthe nose portion |36 and similarly bolted upon the inclined face of thenose portion |36 is a resilient hold down blade 35 which also projectsout over and is flexed down upon` the forward end |38 of the plate |31,as shown in Figure 14. centrally in the underface of the solder feedinghead |35 is a longitudinal slot' I40sized for slidably accommodating aribbon of solderwhich extends therethrough from a yreel |4IspindleduppnL To this-end the magazines I |31 Once this adj ust-l i Milled 'asupporting arm |42which is, in turn, bolted to, and extends upwardlyfrom, the solder feeding head |35. It will be noted by reference toFigure 2O that the reel MI is preferably provided with a removable faceplate |43 held in place 'by thumbscrews |44 and a central bolt |45. Itwill also be noted that the plate |31 forms a closure for the slot |46and as the ribbon e slides forwardly out of the slot |45 it is held downagainst the forward end |38 of the plate |31 by means of the blade |39.

Secured rigidly upon the under face of the plate |31 by means of bolts|46 which extend up into the body of the solder feeding head |55 is aroller housing block |41 provided with an accurate recess |48 the sidewalls of which are vertically slotted as at |49 to receive a short shaft|50 carrying a roller |5|. Directly above the recess |48, the solderfeeding head |35 is provided with an arcuate recess |52 whichcommunicates with the recess |48 through a slot |53 in the plate |31.Drilled into the bottom walls of the slots |45 are recesses |54receiving compression springs |55 which bear against the shaft |59 andurge the roller |5| resiliently upwardly so as to press the ribbon efirmly against a star wheel w operatively mounted in the recess |52 andprimed to a shaft |56 which is journaled in and extends transverselythrough the solder feeding head |35. One end of the shaft |56 isprojected through a grill |51 and is provided at its end with a knurledknob |58. Keyed to the other end of the shaft ||a` is a conventionaloverrunning clutch |59 supportingly engaging a pinion |66 held in placeby a nut 56|.`

The roller housing block |41 is integrally provided with laterallyprojecting horizontal shoulders |52 having upwardly presented slidefaces |63 for operatively supporting a pair of parallel slide bars I 64,I 65, held together at their opposite ends by cross blocks |66, |51, theupper faces of which slide smoothly against the under face of the plate|31. Recessed into and extending between the support block |34 and crossblock |61 is a compression spring |68 for normally urging the bars |54,|55, forwardly. Formed integrally with and projecting forwardly from thecross block |61 is a stop nnger |69 adapted for abutment against theheel of each tip holding finger 61 as it is rotated into top sideposition and index it into alignment with the saw blade s. In thisconnection it should be notedthat the bracket S8 and its supported shell96 are so located that the ball 95 will bear against the upper edge ofthe next succeeding slot 64 to biasV the head 62 and urge the tipholding finger 61 in such indexed position,

Formed integrally with and extending rearwardly from the slide 44 is aboss |16 which projects loosely between bosses |1|, |12, formedintegrally with the base plate 4|, the latter being threadedly providedwith axially aligned adjustment screws |13, |14, respectively, whichbear against the boss |16. By this means the slide 44 can be shifted inor out through a narrow but adequate range of adjustment to line up thestop inger |68 properly with the saw plate S so that when a tip holdingfinger 61 is brought to rest thereagainst the tip :1: is properlypositioned for precisely seated disposition in the tooth recess r. Inorder that this adjustment may be fully precise a conventional verniergauge |15 is provided, as shown in Figures l0, 1l, and 12, although anyother type of gauge may be employed as desired.

Formed integrally with and extending rearwardly from the arm 45 arespaced bosses |16 for rotatably supporting one end of a shaft |11 whichis journaled at its other end in the gusset 46. Pinned to the shaft |11adjacent the gusset 46 is a radial casting |18 provided with a rod-likehandle |13. Similarly pinned to the shaft |11 between the bosses |16 isan angular arm |86 extending forwardly and upwardly to a pointsubstantially above the nose portion |36 of the solder feeding head |35and being at such end integrally provided with a saddle block |8| forclampwise receiving spaced parallel water-cooled leads |82, |83, of adoubly convoluted work coil |34 which depends downwardly therefrom andwill, when in the operative position shown in Figure 1 embrace theprojected end of the tip holding linger Si' which is seated against thestop iinger |59. By rocking the handle |19 downwardly the work coil |34may be raised upout of operative position te clear the work and as itapproaches the lower limit of its travel, the handle |19 will snap intoengagement with a spring detent so that the work coil ltd will be heldin elevated position for as long as may be desired. The leads areconnected to a source of electronic heat energy (not shown).

Rigidly mounted in and extending horizontally from the arm |86 is aheavy pin |86 located for delayed abutment against a rock arm |61pivoted at its lower end on the shaft |11 and provided at its upper endwith a slot |88 for operative engagement with a pin |39 carried by andextending horizontally between the bars |64, |65. Finally, the bar |65is provided upon its upper horizontal face with roch teeth for drivingengagement with the pinion |66.

Preferably, though not necessarily, the slide is integrally providedwith a rearwardly projecting horizontal arm |96 provided with alaterally projecting pintle |9| upon which is mounted a rock arm |92having a handle |93 and downwardly extending long rod |214 which is, inturn, provided in its end with a lateral pin |95 optionally adapted toseat in any one of the gullets of the saw blade s for purposes presentlymore fully appearing. The rod |54 is, however, normally disposed up outof gullet engaging position,

In use a saw plate S is placed upon the spindle 22 and the collar 35clamped down in place as previously described. The slide is thenadjusted horizontally and vertically so that the rim of the saw S willpass through the central space within the work coil H14 with the bottomwall of each recess r in substantially horizontal position. Since theslide can be adjusted up and down it is possible to accommodate anyangle of rake or hook in the saw plate S. A tip holding finger 61 isbrought up against the stop finger |69 and the slide 44 is adjusted sothat the center line of the tip :r is accurately aligned with the centerplane of the sawpl'ate S.' With these few simple adjustments made theproper magazine i3 with the correctsize of tips x is inserted and thehead 62 is rotated until the next succeeding tip holding finger 51 isaligned with the discharge opening I1 by reason of engagement betweenthe forward end of the slot 54 and the ball iti, as previouslydescribed. Thereupon the plunger |59 is pushed in and a tip :c will beejected directly into the tip holding recess 66. As the tip is beingejected it will cam the U-shaped end |58 of the spring |25 outwardly andat the same time be resiliently pushed thereby into stabilized slidingcontact with the inner face ci the clip |23. in entering the recess 5d,the tip will press the oating side plate avremo 18 slightly outwardlyagainst the bias of the spring 65 and be held snugly in place thereby.The floating side plate 18 accommodates and compensates for any of thenormally encountered variations in size and shape between the varioustips a: due to manufacturing tolerances and the like. Of course, agrossly mis-sized or shaped tip` :c should be rejected before placementin the groove ||6 of the magazine ||3. The bottom or seat face of thetip r will stand up out of the recess 90.

The head 62 is then rotated to bring the loaded tip holding finger 61 upinto brazing or indexed position and as this is done the handle |19 isreleased from the detent spring |85 and swung upwardly to lower the workcoil |84 into operative position. Simultaneously, the rock arm |81 isallowed to swing forwardly permitting the bars |64, |65. and the crossblock |61 to slide forwardly so that the stop finger |69 is brought intoplace. This same action rotates the pinion |69 which rotation istransmitted through the clutch |59 to the shaft |56 and star wheel wthereby driving a short length of solder ribbon e outwardly over theindexed tip x. During these operations the particular tooth into whichthe tip a: is to be brazed is disposed upwardly out of engagement withthe indexed tip :r so as not to interfere with the indexing and solderribbon feeding operations. Therefore, the saw plate S is now rotated to`bring the recess r down on the tip squeezing the protruding length ofsolder ribbon z therebetween. Meanwhile, soldering iiux has beenmanually brushed on the tip and exposed faces of the recess r in anyconvenient manner.

Finally, the current is turned on and timed preferably by someconventional automatic means (not shown) and the braze completed in amatter of seconds. Ordinarily, the heat will sever the fused solder fromthe remainder of the ribbonl z but frequently slight filaments remainand the fused iiux also tends to stick the tip in the recess 90. Hence,the rod |94 is shafted downwardly and the pin |95 engaged in andadjacent the gullet of the saw blade s applying somewhat tangentialpressure thereto and freeing the braze'd tip, so to speak. The handle|19 is then swung downwardly again to initial position lifting the workcoil |84 out of the way. As it returns to initial position the pin |86picks up the rack arm |81 shifting the stop finger |61 out of the way.This return motion, however, is not transmitted through the overrunningclutch |59 to the shaft |56, hence the star wheel w and the ribbon zremain stationary.

The saw plate can then be rotated to bring a new tooth into position andthe operation repeated successively until all teeth are tipped. Becausemost available fluxes tend to spatter when heated, the work coil must bemost carefully and thoroughly insulated with chemically and thermallyinert material and, in some cases, it has been found desirable to fold athin strip of mica over the tooth and tip just prior to application ofheat so as to protect the work coil from the spattering flux. It willalso be noted that as the head 62 rotates through its various positions,the used and flux bespattered tipholding finger 61 will dip into thewater bath in the pan 92 and be cleansed, since the fiux dissolves offpromptly in warm water.

By removing the work-supporting spindle 22 4and thereupon taking out thescrews 21, the retainer ring 26 and ball bearing assembly 24, 25,

can be removed. A conventional Work-holding 112 vise (not shown) canthen be mounted by means of the screws 21, or any other conventionalmeans, upon the work-supporting arm |9 for clampwise holding a band saw,which can then be tipped in substantially the same manner as abovedescribed. This is entirely feasible inasmuch as the slide can beshifted vertically up and down through a relatively wide range, therebypermitting a substantially straight section of band saw teeth to betipped` successively in a single clamped set-up within the vise.

It should be understood that changes and modifications in the form,construction, arrangement, and combination of the several parts of themeans for making carbide tipped saws and in the steps of its productionmay be made and substituted for those herein shown and described Withoutdeparting from the nature and principle of my invention.

Having thus described my invention, what I claim and desire to secure byLetters Patent is:

1. A machine for brazing tips in tools which comprises means for holdingthe tool, a magazine for holding a plurality of tips, a movable headhaving a plurality of spaced fingers each adapted for receiving a tipfrom the magazine and moving it into engagement with the tool in theproper position for securement thereto, and means for cleaning eachfinger subsequent to use and prior to re-use.

2. A machine for brazing tips in toools comprising means for holding thetool, a movable tip-receiving fixture, each fixture having a resilientback and side wall for accommodating minor variations in the size ofsuccessive tips, a

magazine for holding a plurality of tips, a manually operable plungerfor transferring a tip from the magazine to the fixture, means formoving the fixture into alignment with the tool and the tip in positionto be brazed thereto, and means for heating the positioned tip and thetool in the immediate regions of their juncture.

3. A machine for brazing tips in tools comprising means for holdingthetool, a magazine for holding a plurality of tips, means for transferringa tip from the magazine to the tool in position to be brazed thereto,means for feeding a predetermined quantity of brazing alloy between thetip and the tool, means for heating the positioned tip and the tool inthe immediate regions of their juncture, and means for moving theheating means into and out of operative position, said last-named meansbeing so connected to the heating means as to have a predeterminedamount of overtravel as the heating means comes to rest in inoperativeposition, and said last-named means being also connected to the feedingmeans so as to actuate the feeding means during return movement afterovertravel.

4, A machine for brazing tips in tools which comprises means for holdingthe too-l, a magazine for holding a plurality of tips, a movable headhaving a plurality of spaced fingers each adapted for receiving a tipfrom the magazine and moving it into engagement with the tool in theproper position for securement thereto, and means for shifting themagazine to any desired position with respect to the head within alimited range of adjustment.

5. A machine for brazing tips in tools comi side, a strip-solder feedingmagazine disposed in outwardly spaced relation to, and in endwisealignment with, the positioned tip-receiving recess, means f-or feedinga predetermined length of strip-solder into the recess, a rotating headoperatively mounted in outwardly spaced relation to the tool and havinga projecting tipholding element located on the head in such manner thatupon rotation of the head the outer end oi the tip-holding element willpass laterally into and through the positioned recess of the tool, astationary magazine mounted adjacent the path of movement of thetip-holding element, and means associated with the magazine foroptionally ejecting a tip and depositing the ejected tip in apredetermined position in the tip-holding element.

6. A machine for brazing tips in tools comprising means for holding thetool stationary in a selected position with the recess into. which thetip is to be brazed positioned outwardly and clear of lateralobstructions so that the tip may be passed freely through the recessfrom side to side, a strip-solder feeding magazine disposed in outwardlyspaced relation to, and in endwise alignment with, the positionedtip-receiving recess, meansl for feeding a predetermined length ofstrip-solder into the recess, a rotating head operatively mounted inoutwardly spaced relation to the tool and having a projecting tipholdingelement located on the head in such manner that upon rotation of thehead the outer end o-f the tip-holding element will pass laterally intoand through the positioned recess of the tool, a stationary magazinemounted adjacent the path of movement of the tip-holding element, meansassociated with the magazine for optionally ejecting a tip anddepositing the ejected tip in a predetermined position in the tipholdingelement, and manually releasable stopforming means located along thepath of the tip-holding element and adjacent to the tool for optionallystopping the tip-holding element during the course of its lateral travelinto the positioned recess so that the tip carried by the tipholdingelement will come to rest in the desired position for brazing with thestrip of solder 14 snugly interposed between the tip and the adjacentfaces of the positioned recess.

7.'A machine for brazing tips in tools comprising means for holding thetool stationary in a selected position with the recess into which thetip is to be brazed positioned outwardly and clear of lateralobstructions so that the tip may be passed freely through the recessfrom side to side, a strip-solder feeding magazine disposed in outwardlyspaced relation to, and in endwise alignment with, the positionedtip-receiving recess, means for feeding a predetermined length ofstrip-solder into the recess, a rotating head operatively mounted inoutwardly spaced relation to the tool and having a projectingtip-holding element located on the head in such manner that uponrotation of the head the outer end of the tip-holding element will passlaterally into and through the positioned recess of the tool, astationary magazine mounted adjacent the path of movement of thetip-holding element, means associated with the magazine for optionallyejecting a tip and depositing the ejected tip in a predeterminedposition in the tip-holding element, and a vessel adapted to be filledto a predetermined level with a cleansing bath, said vessel being alsopositioned along the path of movement of the tip-holding element so thatupon rotation of the head subsequent to manual release of thestop-forming means the tip-holding element will pass into the cleansingbath.

CLAUD E. BRAKE.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 1,699,091 Butler Jan. 15, 1929 1,876,821 Dugen Sept. 13, 19321,884,683 Hermani Oct. 25, 1932 1,885,584 Brisbois Nov. 1, 19322,057,037 Kronquest Oct. 13, 1936 2,311,433 Dershem Feb. 16, 19432,326,674 Pavitt Aug. 10, 1943 2,419,484 Danziger Apr. 22, 19472,477,129 Johnson July 26, 1949 2,481,081 Celva Sept. 6, 1949

